<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>useFlex</title>
    <style type="text/css">
        section{
            display: flex;
            width: 60%;
            height: 150px;
            background-color: pink;
            margin: 0 auto;
        }
        section > div{
            border: 1px black dotted;
            text-align: center;
        }

        section div:nth-child(1){
            width: 100px;
            height: 150px;
            background-color: red;
        }
        section div:nth-child(2){
            flex:1;
            background-color: white;
        }
        section div:nth-child(3){
            width: 100px;
            height: 150px;
            background-color: blue;
        }

        p{
            display: flex;
            width: 60%;
            height: 150px;
            background-color: pink;
            margin: 100px auto;
        }

        p > span{
            flex: 1;
            text-align: center;
            border: 1px black dotted;
        }
    </style>
</head>
<body>
<div>
    <section id="roo">
        <div class="inn">1</div>
        <div class="inn">2</div>
        <div class="inn">3</div>
    </section>

    <p>
        <span>1</span>
        <span>2</span>
        <span>3</span>
    </p>

</div>
</body>
</html>
